paroxetine hydrochloride

paroxetine hydrochloride

(pah rox' a teen)

Paxil, Paxil CR, Pexeva

Pregnancy Category C

Drug class

Antidepressant

Therapeutic actions

Potentiates serotonergic activity in the CNS, resulting in antidepressant effect.

Indications

·        Treatment of major depressive disorder

·        Treatment of OCD

·        Treatment of panic disorders

·        Treatment of social anxiety disorder (social phobia)

·        Treatment of generalized anxiety disorder

·        Treatment of PTSD

·        Treatment of PMDD

·        Unlabeled uses: Treatment of diabetic neuropathy, headaches, hot flashes

Contraindications and cautions

·        Contraindicated with MAOI use.

·        Use cautiously in the elderly, with renal or hepatic impairment, pregnancy, lactation, suicidal patients.

Available forms

Tablets—10, 20, 30, 40 mg; CR tablets, 12.5, 25, 37.5 mg; suspension—10 mg/5 mL

Dosages

ADULTS

·        Depression: 20 mg/day PO as a single daily dose. Range, 20–50 mg/day. Or 25–62.5 mg/day CR tablet.

·        OCD: 20 mg/day PO as a single dose, may increase in 10-mg/day increments; do not exceed 60 mg/day.

·        Panic disorder: 10 mg/day, increase in increments of 10 mg/wk; usual range: 10–60 mg/day. Or 12.5–75 mg/day CR tablet; do not exceed 75 mg/day.

·        Social anxiety disorder: 20 mg/day PO as a single dose in the morning. Or, 12.5 mg/day PO CR form. May increase up to 60 mg/day or 37.5 mg/day CR form.

·        Generalized anxiety disorder: 20 mg/day PO as a single daily dose. Range, 20–50 mg/day.

·        PMDD: 12.5 mg/day PO as a single dose in the morning. Range, 12.5–25 mg/day.

·        PTSD: 20 mg/day as a single dose. Range, 20–50 mg/day PO.

·        Switching to or from an MAOI: At least 14 days should elapse between discontinuation of MAOI and initiation of paroxetine therapy; similarly, allow 14 days between discontinuing paroxetine and beginning MAOI.

PEDIATRIC PATIENTS

Safety and efficacy not established.

GERIATRIC PATIENTS OR PATIENTS WITH RENAL OR HEPATIC IMPAIRMENT

10 mg/day PO; do not exceed 40 mg/day. Or 12.5 mg/day CR tablets; do not exceed 50 mg/day.

Pharmacokinetics

Route	Onset
Oral	Slow

Metabolism: Hepatic; T_1/2: 24 hr

Distribution: Crosses placenta; enters breast milk

Excretion: Urine

Adverse effects

·        CNS: Somnolence, dizziness, insomnia, tremor, nervousness, headache, anxiety, paresthesia, blurred vision

·        CV: Palpitations, vasodilation, orthostatic hypotension, hypertension

·        Dermatologic: Sweating, rash, redness

·        GI: Nausea, dry mouth, constipation, diarrhea, anorexia, flatulence, vomiting

·        GU: Ejaculatory disorders, male genital disorders, urinary frequency

·        Respiratory: Yawns, pharyngitis, cough

·        Other: Headache, asthenia

Interactions

Drug-drug

·        Increased paroxetine levels and toxicity with cimetidine, MAOIs

·        Decreased therapeutic effects of phenytoin, digoxin

·        Decreased effectiveness of paroxetine with phenobarbital, phenytoin

·        Increased serum levels and possible toxicity of procyclidine, tryptophane, warfarin

·        Risk of serotonin syndrome (hypertension, hyperthermia, mental status changes) if used with SSRIs

Drug-alternative therapy

·        Increased sedative-hypnotic effects with St. John's wort

Nursing considerations

Assessment

·        History: Hypersensitivity to paroxetine, renal or hepatic impairment, seizure disorder; pregnancy, lactation

·        Physical: Orientation, reflexes; P, BP, perfusion; R, adventitious sounds; bowel sounds, normal output; urinary output; liver evaluation; LFTs, renal function tests

Interventions

·        Administer once a day in the morning.

·        Shake suspension well before using.

·        Ensure that patient swallows CR tablets whole; do not cut, crush, or chew.

·        Limit amount of drug given to potentially suicidal patients.

·        Abruptly discontinuing drug may result in discontinuation symptoms (agitation, palpitations); consider tapering.

·        Advise patient to avoid using if pregnant or lactating.

Teaching points

·        Take this drug exactly as directed and as long as directed. Shake suspension well before using. Swallow controlled-release tablets whole; do not cut, crush, or chew.

·        Abruptly stopping the drug without tapering the dose may cause symptoms including agitation and palpitations.

·        This drug should not be taken during pregnancy or when nursing a baby; using barrier contraceptives is advised.

·        You may experience these side effects: Drowsiness, dizziness, tremor (use caution and avoid driving or performing other tasks that require alertness); GI upset (eat frequent small meals, use frequent mouth care); alterations in sexual function.

·        Report severe nausea, vomiting; palpitations; blurred vision; excessive sweating.

Adverse effects in Italic are most common; those in Bold are life-threatening.